The present invention relates to data communication systems and more particularly to systems and methods for managing limited network capacity as well as systems and methods for handling data traffic having different priority levels.
The demand for data communication services is growing at an explosive rate. More and more residential and business users are being connected to the Internet. Furthermore, the types of traffic being carried by the Internet are shifting towards high bandwidth applications such as voice and video traffic.
To accommodate the growth and demand for Internet services, service providers are rapidly installing network switching devices such as routers and upgrading physical media throughout their networks. For user access, dial-in lines are being replaced by DSL, cable modem, and broadband fixed wireless. Increasingly, the network backbone exploits optical fiber physical media. Fiber is also being deployed further toward the network edge so that, for example, data over cable networks are being transformed into HFC (highbred fiber cable) networks. Yet even with these advances in data networking technologies and the high level of investment by service providers, demand for network bandwidth continues to outpace supply.
One technique that may be applied to expand the effective throughput of a network is data compression. Data compression techniques take advantage of redundancy inherent in many types of data. For example, text documents may be compressed by assigning a variable number of bits to individual letters depending on their frequency in the document. If letters that appear frequently are encoded by a very small number of bits, this can greatly reduce the amount of data required to store and/or communicate the document. More sophisticated techniques can be used to encode voice and/or video traffic.
However, the processing necessary to perform compression at the data source and decompression at the data sink (destination) may add an intolerable level of delay. This delay may be insignificant for certain types of data traffic such as email, tolerable but undesirable for web downloading, and intolerable for real time voice or video communication.
What is needed are systems and methods for data communication that take advantage of the capacity increasing capabilities of data compression technology while protecting delay sensitive traffic or other high priority traffic from the adverse consequences of compression processing calculations.